Boiler for evaporating or heating liquids



Jan. 14, 1930. A. HITCHCOCK-SPENCER 1,743,913

BOILER FUR EVAPORATING QR HEATING LIQUIDS Filed March 27, 1929 5Sheets-Sheet l av /WM Jaln. 14; 1930. A. L. HlTCHcocK-sPENcER 1,743,913

BOILER FOR EVAPORATING 0R HEATING LIQUIDS Filed March 27, 1929 v 5Sheets-Sheet 2 Imam/70 Jan. 14, 1930. A. L. HiTCHCOCK-SPENCER 1,743,918

BOILER FOR EVAPORATING 0R HEATiNGLIQUIDS Filed March 27, 1929S'Sheets-Sheet 3 Jan. 14, 1930. A. L. HITC HCOCK-SPENCER ,7

BOILER FOR EVAPORATING OR HEATINGLIQUIDS Filed-March 27, 1929 5Sheets-Sheet 4 Jan. I4, 1930. 1 A. L. HITCHCOCK-SPENCER 1,743,918

I BOILER FOR EVAPORATING QR HEATING LIQUIDS I Filed March 27, 1929 5Sheets-Sheet 5 I Z e efl""' Patented Jan. 14, 1930 UNITED PATENT OFFICEARTHUR LINCOLNE' HiroH'oocK-sPnNcER, or AsiiwELL, NEAR BAL'DocK, ENGLANDnamin Fort EvA ronA'rINe on HEATING LIQUIDS Application filed March-27g1929, Serial No; 350,228, and in Great Britain March 23, 1928.

This invention'relates-toboilers tor evaporating or heating liquidshaving water-tubes in the fire-box but particularly to vertical boilersof this type in which such water-tubes are arranged inthe term of one ora plurality of nests of comparatively small diameter tubes extendingacross the fire-box andconimunicating at each end withthe' surroundingwater space. i v u In practicethese tubes are so grouped as leaveasector-shaped passage relative to the curved wall of the fire-box whichconstitutes considerable dead space atueach vertical side of thefire-box and between adjacent nests of tubes up which the products ofcombustion can flow with the freedom necessary for the creation of anadequatedraught.

One ofthe primary objects of the present inventionis to obviate some'ofthe heat losses resulting from the presence of these dead spaces andpreferably in such a manner as to render unnecessary the employment ofan excessive member of closely grouped crosstubes.

Broadly the invention consists of a boiler ior evaporating orheatingliquids having one on more nests of water-tubes extending acrossthe combustion chamber or fire-box in which a solid or hollow member oir'efractory or i 30 other material is locatedin one ormore of theaforesaid normally deadi spaces and'disposed in slightly spaced relationfrom the iire-box wall to thus permit the products'of combustion to flowt'herethru, for the purpose 3 0i usefully absorbing heat from andotbaffling the gases: which pass through such dead spaces.

By makingt'he members according to this invention hollow1 air steamor'other gases may it 40 be introduced'andbe thereby heated for anyuseful purpose such as primary and/or sec ondary air for supportingcombustion in the same or one or more auxiliary boilers or for heatingwaste or live gases or air for use in as heating one or more auxiliaryboilers or heaters or for drying and feed water" heating.

Where the hollow membersare to be used for heating air orother gas andwheresuch air orother gas is to be used-in supporting 5001" addingtocombustion'in the firebox of the same boiler the lower ends of thehollow members may be shaped to form nozzles or otherwise provided withoutlets for causing the heated air or other gas to be projected into thefire-box.

For ease in assembly each member may be built up from a plurality ofhollow sections and such sections may either communicate to form acontinuous passage through the centre of the member or each section mayform a separate and noncommunicating chamber.

The elements which are physically independent of the fire-box wall maybe suspended in position from the fire-box crown by means of a centraldepending rod or tube which may conveniently extend through the fire-boxcrown, the water spaceand the opposite crown plate of the boiler. WVherea tube is used for this'purpose such tube may be used for theadmissioninto the interior of the element or each section thereof of thewater air steam or other gas to be heated therein. Where air or'gas isto be introduced into each element and usedsubsequen'tly after heatingas primary and/or'secondary air or burnt the same may be admitted to theinteriors of the elements under pressure Orsuction such as by a suitableblower or exhauster.

Alternatively the interior of each element or the sections of eachelement may communicatewith the exterior of the boiler or heater bymeans of one ormore pipes extending laterally through the sides of theboiler or through the base or furnace or down the Lip-take.

As a further alternative the members accordingto this invention beconstructed toform part of asuperheater for which purpose tlie" suaerheating tubes are arranged withinthe thickness of each member so thatsuclitubes will absorb some of the heat from such members. If desiredthese tubes may constitute the means or a part of the means forsuspending the members'withi-n the firebox. Alternatively such tubes mayconstitute water tubes forthe purpose of assisting theevaporation orheating of the water.

Themembers according to this invention maybe either parallel or taperedin a vertical direction the thickest part of each member bein either atthe top or at the bottom. By suita 1y shaping these members the velocityof the gases past the heating surface will be increased without undulyrestricting the draught.

In order that the invention may be clearly understood and carried intoeffect several examples will now be described by aid of the accompanyingdrawings in which Fig. 1 is a vertical section through a vertical boilerin which the members according to this invention are solid and built upfrom shaped sectionsof refractory material supported from the fire-boxcrown by means of bolts.

Fig. 2 is a transverse section showing similar solid members butillustrating a modified method of supporting the same in position.

Fig. 3 is a view similar to Fig. 1 illustrating the use of hollow builtup members supported by tubes which extend through the fire-box crownthe water-space and the top flange of the boiler.

Fig. 4 is a transverse section through the same showing atop plan viewof the members.

Fig. 5 is a vertical section through a boiler showing in elevationmodified forms of hollow members adapted to be constructed of metal andused for the heating of steam or other gases to be used exteriorly ofthe boiler.

Referring now to Fig. 1 the members illustrated are composed of aplurality of solid shaped pieces a of refractory material which arethreaded upon suitably long bolts 6 which are aflixed by their upperends to the fire-box crown 0 so as to depend therefrom into the spacebetween the fire-box sides at and the nests of water-tubes e.

In the modification illustrated in Fig. 2 the members composed of thesections a are supported in position by means of lateral bolts Suchlateral bolts may however also be used in conjunction with the dependingbolts Z) illustrated in Fig. 1 and serve the purpose of impartinglateral stability to the members.

The solid members in the examples just described serve the purpose ofheat exchanging elements only heat being taken up from the ascending hotgases and imparted to the adjacent water-tubes e by radiation.

In the example illustrated in Figs. 3 and 4 the nests of tubes e arearranged in two vertical groups each group comprising three superimposednests thus leaving three normally dead spaces for the free passage ofthe hot gases. In each of these spaces is arranged a member according tothis invention and in the example illustrated these members, which arebuilt up from refractory sections a are hollow and form a series ofcommunicating spaces 9 throughout the length of each member. The hollowinteriors of these members are adapted in the present example to besupplied withsteam, air or other gases which is introduced by way ofpipes h serving also as a means for supporting the members in position.These pipes extend to the outside of the boiler through the fire-boxcrown c and by their outer extremities are connected to the requiredsource of supply or left unconnected and open for the admission of airby natural draught. Such air may however be forced in under pressure bymeans of a blower or be induced in by suction.

Lateral lugs 11 are formed on the members to assist the same inmaintaining their positions relatively to the water-tubes.

The lower end of each member is composed of a metal casting, forging orthe like j having each an opening 74 so shaped as to project the heatedair, gas or the like from the interiors of the members into the interiorof the fire-box. In the case of a boiler heated by waste-heat some ofthe gases may be admitted from the lower end of the fire-box and theremainder by way of the inlet openings 70. This arrangement is alsosuitable for the admission of pre-heated primary and/or secondary airinto the combustion chambers of coal or oil fired boilers.

In the modification illustrated in Fig. 5 the members, which areindicated at Z are each in one piece, hollow, and composed of metal.They are supported in position by means of lateral pipes on formingoutlets for the air or other gases heated within the hollow interiors ofthe members. Suitable inlets, not shown, for such gases may also beprovided. These members Z are primarily intended for use in heating airor gases for use exteriorly of the boiler but the same may of course bereturned to the fire-box of the boiler for any suitable purpose. Suchmembers may of course be composed of a number of sections andconstructed of refractory material instead of metal.

As a further alternative the members according to this invention may beconstructed to form part of a superheater for which purpose thesuperheating tubes are arranged within the thickness of each member sothat such tubes will absorb some of the heat from such members.constitute the means or a part of the means for suspending the memberswithin the firebox. Alternatively such tubes may constitute water-tubesfor the purpose of assisting the evaporation or heating of the water.

Claims:

1. In a vertical flue boiler having a firebox substantially circular incross section and a nest of water tubes extending transversely acrosssaid fire-box and defining in conjunction with the wall of said fire-boxa vertical sector-shaped passage, a combined baffling and heat absorbingmember disposed in said passage and spaced from said fire-box If desiredthese tubes may wall and having a connection with the firebox whereby itis supported therefrom;

2. In a vertical flue boiler having a firebox substantially circular incross section and a nest of water tubes extending transversely acrosssaid fire-box and defining in conjunction with the wall of said fire-boxa vertical sector-shaped passage, a combined bafliing and heat absorbingmember disposed in said passage and spaced from said fire-box wall andhaving a connection with the fire-box whereby it is supported therefrom,said member being composed of a plurality of assembled sections.

3. In a vertical flue boiler having a firebox substantially circular incross section and a nest of water tubes extending transversely acrosssaid fire-box and defining in conjunction with the wall of said fire-boxa vertical sector-shaped passage, a combined baffling and heat absorbingmember disposed in said passage having fluid connections whereby theabsorbed heat is transmitted to said fluid.

4:. In a vertical flue boiler having a firebox substantially circular incross section and a nest of water tubes extending transversely acrosssaid fire-box and defining in conjunction with the wall of said fire-boxa vertical sector-shaped passage, a combined bafliing and heat absorbingmember disposed in said passage in spaced relation to the firebox walland having fluid connections whereby the absorbed heat is transmitted tosaid fluid.

5. In a vertical flue boiler having a firebox substantially circular incross section and a nest of water tubes extending transversely acrosssaid fire-box and defining in conjunction with the wall of said fire-boxa vertical sector-shaped passage, the combination of a combined bafliingand heat absorbing member disposed in said passage, means to deliverfluid to be heated to the hollow interior of the member, and meansformed at the lower end of the member to deliver the heated fluid to theinterior of the firebox.

In testimony whereof I affix my signature.

ARTHUR LINCOLNE HITCHCOCK-SPENCER.

